Beware of the Hottest New Grocery Scam

Celebrity chefs have made olive oil a $720 million business in the U.S., but a new book is blowing the lid off an industry that might be built in part on the backs of crooks.

That's the argument Tom Mueller makes in Extra Virginity: The Sublime and Scandalous World of Olive Oil.

“I was sitting in a dark bar with an undercover cop in Italy, and he was telling me about deals being cut with high-level politicians and millions of dollars in EU subsidies being misappropriated,” Mueller told the New York Post. “He was speaking in this hushed tone, and I had to laugh, because this was not black-market plutonium or drugs, this was olive oil.”

Mueller contends that because true olive oil is so pricey to produce, some companies have taken to doctoring bottles with chemicals and disguising cheaper oils with added flavoring.

Then they slap on fancy labels with buzzwords like "Made in Italy" and "Cold-pressed" and ship them to stores without any rigorous quality control from the FDA, he says.

It wouldn't be that big of a deal, except the knockoffs offer far fewer of the health benefits that made olive oil such a cash cow to begin with.

The best way to tell a fake from the real thing?

Read on to find out.

Consumers spend an incredible $720 million per year on olive oil, according to the California Olive Oil Council. But, clearly, not all olive oil is created equally.

Follow tips from COOC to be sure you know what you're buying:

Bottle color matters. True olive oil should be kept cool so bottles will be darker in color to extend shelf life.

Check the label. States like California place quality control labels from the COOC on all bottles of oil produced in the state. To earn a seal, a taste panel puts it through a vigorous chemical test.

Where you shop matters. Olive oil is definitely one of those products you never want to buy generic. Not all retailers keep a close eye on where they're sourcing their oils, so look for higher quality oils at specialty markets. When in doubt, check the label yourself to see its origin.

And don't believe everything you read. The FDA can't catch every bottle that hits store shelves proclaiming to be "Extra virgin" or "cold pressed," Mueller warns. If all else fails, try taking a whiff. True EVOO should smell a little fruity.